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Created DVD but picture quality not too good....

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skybox
Created DVD but picture quality not too good....
on Nov 12, 2002 at 6:49:45 pm

Greetings, well, I finally managed to create my first DVD, and since I can't get 2 hours of video on 1 disk, split my football footage into 2 halves on 2 discs. Nothing is wrong as far as video quality with the camcorder in case anyone wonders. The video looks perfectly fine during capture process.

Here's the problem: When I play it back, I don't know how to explain this, but it is kind of a "strobe" type effect when the camera pans on a running or passing play and man it plays havoc with your eyes. There is definitely a kind of pixelization following the players on the screen which is terrible to watch. Now mostly this appears when there is a lot of movement on the screen like running or passing plays. Audio comes out fine, but obviously something not right with picture. The picture moves smoothly, no jerkiness or anything, just this weird strobe effect. I am sure it is related to picture quality.

Now I have tried capturing at 5000, 6000 and even 8000 bps (once at 9800 kbps) hoping on this last try that it would improve but I can't find the magic setup. I am using a Radeon 7500 capture card, 1.4 gig Athlon processor, Win2k Pro and I have tried audio at 112, 128, 290, 384 kbps but that hasn't seemed to really matter. I thought maybe the audio file was so large that it was affecting video quality (eating up space for the video) I have tried capturing as both an AVI and as MPEG2, and 1 time I had good video quality, the sound was bad, but I can't remember what settings I used and if I recall correctly, it was when I captured as an AVI file rather than MPEG2. Does that make any sense?

I have tried this about 15 times, and am banging my head against the wall trying to figure this out. Has anyone out there had any experiences like this and how did you solve it. I am using DVD Video Studio 6 and DVD Workshop for the capture/edit process.
Anyone have any ideas about this??



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skybox
Re: Created DVD but picture quality not too good..
on Nov 13, 2002 at 2:34:50 pm

OK, played around a little bit last nite, and decided to record a couple songs from a Mellencamp tape I recorded from MTV. Recorded 6 minutes of video at 7500kbps VBR, and audio set to 384kbps @ 48000 hz and recorded as an MPEG2 file. Played it back on my DVD player, and picture looks just fine. I am thinking the problem I am having with the football stuff is directly related to all the motion (i.e. fast action) which is playing havoc with the picture quality. Sure would be nice to be able to remove that jitter or strobe effect but I just don't know what to do to eliminate it.


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John Q
Re: Created DVD but picture quality not too good..
on Nov 14, 2002 at 4:57:40 am

Television is interlaced video, which means half the lines are painted on one pass (field), and the other half are painted on the second field. For the United States, it's NTSC 60 fields/second, which equals 30 frames/second, with the lower field first.

Your computer screen is progressive scan, which means that all lines are painted on each field/frame.

Your normal camcorder also records interlaced video. (George Lucas used more expensive progressive scan 24p cameras for Star Wars II.)

Now comes the question of how to encode it when you digitize it. If you're creating a DVD for standard television, then you're designing it for an interlaced display, and should capture the video in interlaced mode, lower field first for NTSC. Then edit the video and author the DVD. Playback of the DVD on your computer will not look very good, exhibiting the combing effect on objects in motion. That's because your computer display is progressive scan, although some pc dvd players do a better job of deinterlacing than others. Playback of the interlaced video on your television will look fine, if your interlace mode matches your television's interlace mode. If your DVD's video is encoded with the wrong field first, then you'll see really excessive combing there.

Of course, all of this will change when we finally convert to digital high definition television.


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jra111
Re: Created DVD but picture quality not too good..
on Nov 14, 2002 at 6:54:30 pm

When will high definition happen?


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John Q
Re: Created DVD but picture quality not too good..
on Nov 15, 2002 at 4:51:38 am

You can buy high definition televisions (HDTV) now, but they're big and expensive. For source material, you can use a progressive scan DVD player, and there are a few broadcast and satellite dish channels in HD mode.

The FCC wanted it to happen by now and stop allowing the broadcast of analog interlaced 4:3 television, but it's turning out harder to wean us off the existing analog tv broadcasts than the FCC expected.


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skybox
Re: Created DVD but picture quality not too good..
on Nov 19, 2002 at 5:55:50 pm

So, John Q, what you are saying is that I probably used the wrong field order when I recorded the video? That could be, I used Field A, should I have used Field B instead?

One thing I have noticed during the last 2 attempts, I found that if I do frame based capture and frame based rendering, I get excellent results as far as picture quality, but my god, the rendering times are horrific. The one I did last night for a 55min video took over 10 hours to render using frame based rendering.

Do you think I would have better luck choosing Field B? I guess I will try it and see what happens. God only knows I have already done this about 10 times so far trying to find what works best.


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John Q
Re: Created DVD but picture quality not too good..
on Nov 20, 2002 at 2:51:21 am

I'd try Field B. It sounds like "Frame Based" deinterlaces the video, which is a very time consuming process.


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skybox
Re: Created DVD but picture quality not too good..
on Nov 21, 2002 at 4:34:10 pm

That appears to have done it!. Finally got decent picture quality using Field B. Plus that shortens up the render time.
I can't believe how time consuming this whole operation is.

Thanks for the help guys.


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Daniel A. Reynolds
Re: Created DVD but picture quality not too good..
on Nov 24, 2002 at 9:24:45 am

I get the pixelazation you described around red football players on a green field shot on a digital camera in progressive scan mode. I've tried to encode DVD mpeg 2 at 7000kb vbr with both upper field first and lower field first. I still have the pixelazation halo aroud the players. Despite the fact that the DV pinnacle avi video I am using in Premiere 5.1c are set as lower field first, the Pinnacle DVD encoding shows a preset at upper field first. This seems to play back fine after I burn the DVD and play either on TV or computer screen (except with the pixel halo). When I try encoding the mpeg 2 at lower field first , it doesn't get any better. Still has pixelization. This is my main problem. I need help here. Oh yes when the original footage is shot with analog camera, I don't have the pixelation problem.


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